OAI/Geometry/RCD/Sobolev/TorsionSuperlevel.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

Nonlinear superlevel inequality for the Dirichlet torsion solution

Bounded two-level tests, rather than a prior integrability assertion for an unbounded power of the solution, justify each use of Sobolev and Hölder.

  1. theorem OAI.RegularPointCoordinates.level_superlevel_measure_le line 20

    Source documentation

    The bounded level moment controls the measure of the upper superlevel.

    theorem level_superlevel_measure_le {X : Type*} [MeasurableSpace X]
        (ν : Measure X) [IsFiniteMeasure ν] {u : X → ℝ} (hu : Measurable u)
        {k l p B : ℝ} (hkl : k < l) (hp : 0 < p)
        (hbound : (∫ x, levelClip k l (u x) ^ p ∂ν) ≤ B) :
        ν.real {x | l ≤ u x} ≤ B / (l - k) ^ p := by
    …

    Mentions: OAI.RegularPointCoordinates.levelClip

  2. theorem OAI.RegularPointCoordinates.torsion_superlevel_le line 55

    Source documentation

    The superlinear measure recurrence underlying the torsion height bound.

    theorem torsion_superlevel_le (Ω : Set X) (hΩfin : μ Ω ≠ ∞)
        (u : SobolevSpace.dirichlet μ hQ Ω)
        (hsolve : ∀ φ : SobolevSpace.dirichlet μ hQ Ω,
          energyForm μ hQ u.val φ.val = ∫ x in Ω, SobolevSpace.toLp μ hQ φ.val x ∂μ)
        {d C : ℝ} (hd : 1 < d) (hC : 0 ≤ C)
        (hsob : ∀ φ : SobolevSpace.dirichlet μ hQ Ω,
          (∫ x in Ω, |SobolevSpace.toLp μ hQ φ.val x| ^ (2 * d) ∂μ) ^ (1 / d) ≤
            C * energyForm μ hQ φ.val φ.val)
        {k l : ℝ} (hk : 0 ≤ k) (hkl : k < l) :
        (μ.restrict Ω).real {x | l ≤ SobolevSpace.toLp μ hQ u.val x} ≤
          C ^ (2 * d) *
            ((μ.restrict Ω).real {x | k < SobolevSpace.toLp μ hQ u.val x}) ^ (2 * d - 1) /
    …

    Mentions: OAI.RegularPointCoordinates.SobolevSpace.dirichlet, OAI.RegularPointCoordinates.energyForm, OAI.RegularPointCoordinates.SobolevSpace.toLp